Iranian Journal of Basic Medical Sciences
Year:2006 | Volume:9 | Issue:3 (31)|Papers Count:11

Objective: Bacteria of species Streptococcus pyogenes are a human pathogen, causing serious invasive infections. The culture method remains the standard way for its isolation and identification. Due to the accessible facilities, medical laboratories employ different methods in this way. In present study the most common methods have been statistically interpreted.Materials and Methods: A total of 159 beta-hemolytic streptococci isolated from different samples were tested for hemolysis potency, sensitivity to bacitracin (BC) or sulfametoxazole/trimethoprim (SXT) and Voges-proskauer (V.P). Based on L-pyrrolidonyl-beta-naphthylamide (PYR) test, the positive predicted value (ppv), negative predicted value (npv) and sensitivity (sen) of each test were calculated.Results: The ppv, npv and sen. of beta-hemolysis on sheep blood agar (SBA) for identification of S. pyogenes were 75, 89 and 89% respectively. It was 76, 89 and 53% for banked human blood (BHB). For BC test the above mentioned criteria were 52, 70 and 89% and also for VP test 57, 89, and 94%. Finally SXT test with 49, 47 and 63% demonstrated the least practical identification value.Conclusion: The PYR test is considered the most reliable biochemical test for identification of S. pyogenes among other beta hemolytic streptococci. If it is not available, combining of hemolysis ≥3mm with BC≥10mm has presumptive identification value of 89%. It was realized that the hemolytic activity of this bacterial species on BHB is documented and equal to a potent hemolysis on SBA. The VP test with 89% value is a suitable test to rule out its presence; but the accuracy of SXT test result is limited.

Objective: The incidence of urinary stones is very high in population. Treatment of patients with kidney stones in primary stages can reduce the side effects and also may prevent the surgical operations and postoperative complications. Several effects have been reported for Nigella sativa seeds; they include: anti analgesic, anti inflammatory, lowering serum lipids, increasing glutathione in kidney and repairement of kidney tissues after nephrotoxicity. The aim of this study was to investigation the effects of the ethanolic extract of N. Sativa seeds on kidney stones in rat.Materials and Methods: Thirty two Wistar rats weighed 200±10g were randomly divided into 4 groups: Group an as intact control was received tap drinking water for thirty days. Group B (ethylene glycol control), groups C and D as experimental animals all were received 1% (v/v) ethylen glycol in drinking water for 30 days. Furthermore group C was also treated with 250 mg/kg B.W N. sativa ethanolic extract for 30 days, while group D was also treated with 250mg/kg B.W N. sativa extract from 14th day through the end of the experiment. Twenty four hour urine samples were collected on the 0,7th, 14th and 30th days of the study, when each animal was kept in a metabolic cage. After 30 days all rats were killed by guillotine and kidneys were removed and sections were prepared with routine histological techniques; slides were examined under light microscope to count calcium oxalate deposits.Results: The results showed that the number of calcium oxalate deposits were significantly increased in group B vs. A (p<0.001). The number of deposits in group C and D were significantly less than group B (p< 0.05); while the number of calcium oxalate deposits in group C and D in comparison with group A were statistically insignificant. The calcium oxalate concentration in urine at the end of the study was increased significantly in group B vs. A (p<0.001) but decreased in group C (p<0.001) and D (p<0.05) when compared with group B.Conclusion: The result of this study demonstrated that treatment of rats with ethanolic extract of N. sativa has reduced the number of calcium oxalate deposits in both groups of treated animals. Therefore; it may have beneficial effects in treatment of urinary stones in patients.

Objective: Ventilation is 5-6 lit/min at rest, whereas it reaches 150 lit/min during exercise. A long time investigators noticed breath exciting and involving factors, they were proposed to involve several factor. Blood potassium and lactate concentration are contributing factors in increasing the ventilation .The correlation coefficient of ventilation and potassium, lactate is problem which they are discussing about them. This study will test to determine relationship between those factor and ventilation.Materials and Methods: To study this, 15 male volunteer athletes were chosen. They exercised with ergo meter as incremental exercise to extreme fatigue. The exercise was started with 50 watts, and was continued with 25 watts increase at the end of each 3 minute during exercise. Venous blood sample was obtained before exercise and at the end of each 3 minute during exercise.Results: All of the three parameters ventilation, lactate, and potassium increased with work load increments. The pattern of increases was non-linear in all these parameters. The correlation coefficient of ventilation and potassium curves were calculated as r=0.99 and ventilation and lactate curves as r=0.97.Conclusion: Thus our results show that both lactate and potassium are related in increasing ventilation during incremental exercise.

Objective: Bronco constriction is induced by exercise. There are several studies on pulmonary function in athletes during exercise, but there is not a specific study on basketball athletes. The objective of this study was to evaluate the pulmonary function changes during basketball in professional players.Materials and Methods: This study was a before and after study on spirometric parameters during basketball play. Respiratory function was assessed in participants before and 6 to 9 minutes after exercise with a spirolab 2. The study was conducted in three groups, National team of basketball as professional athletes, university team of basketball as semi-professional athletes and medical students as non-athletes group.Results: Thirty five professional athletes, 12 semi-professional athletes and 34 non-athletes participated in this study. Overall, forced vital capacity (FVC) was significantly decreased after exercise (p=0.000), but this change was significant in professional athletes (p=0.05). Although forced expiratory volume in 1 second (FEV1) didn’t have significant changes after exercise, there was a significant reduction in this parameter among professional athletes. There were not any significant changes in other spirometric parameters. The reduction in FVC and FEV1 were not more than 6%.Conclusion: We concluded that changes in pulmonary function parameters in professional basketball players were more than semi-professional and non-athletes people.

Objective: Piper nigrum (Black pepper) from Piperaceae is main constituent of food spice and piperine as its main component increases bile and small intestine secretions, but reduces the gastric emptying and increases intestine transit time in rat and mouse. In traditional medicine, black pepper is used for relief of menorrhalgia in women but this effect has not been evaluated scientifically. The study was performed to investigate the effect of black pepper fruit aqueous extract on rat non-pregnant uterus contractions and the mechanism(s) of its action.Materials and Methods: Aqueous extract of black pepper was prepared by adding 10 g of black pepper powder to 200 ml of boiling distilled water for 15 min and after filtering, solvent was evaporated. Uterus was dissected from non-pregnant adult rat (Wistar) and in an air bubbled De Jalon solution; contractions were recorded isometrically under 1 g tension.Results: Cumulative concentrations of black pepper aqueous extract (0.125, 0.25, 0.5, 1 and 2 mg/ml) reduced the uterus contractions induced by KCl (60mM) and oxytocin (10mU/ml) dose dependently (p<0.0001). The spasmolytic effect of extract on the KCl-induced contractions was unaffected by L-NAME (100μM) but rather increased by phentolamine (1μM) and naloxone (1μM). However, propranolol (1μM) reduced the extract spasmolytic effect significantly (p<0.01–p<0.0001). In calcium free De Jalon solution with high potassium (60mM), extract (0.0312, 0.625, 0.125 and 0.25 mg/ml) reduced the contractions induced by cumulative concentrations of calcium chloride (0.1-0.5mM) dose dependently (p<0.05– p<0.0001).Conclusion: Our results suggest that the spasmolytic effect of black pepper aqueous extract on rat uterus was mediated via voltage dependent calcium channels and also β-adrenoceptors could be involved in this action. However, the α-adrenoceptors, opioid receptors and nitric oxide generation were not involved. Our results may support the usage of black pepper for relief of menorrhalgia in women.

Objective: WHO remarked Leishmaniasis as a world wide hygienic problem with a highly considerable prevalence in Iran. Mashhad is known as one of the most important foci of the disease in our country. Different responses to medical treatment and various prognosis of patients with cutaneous leishmaniasis as well as the possible role of NK cells in prognosis prompted us to evaluate the percentage of these cells through determining CD16+56 marker by flow cytometry in different groups of patients.Materials and Methods: In this prospective study conducted in Ghaem Hospital and Bu Ali Research Institute, Mashhad University of Medical Sciences from August 2001 to October 2002, 36 patients with confirmed cutaneous Leishmaniasis were involved .Blood samples collected from them before and after treatment, 29 cases out of these patients successfully carried out the survey and 7 patients excluded for different reasons. Lymphocytes with CD16+56 markers were counted using different monoclonal antibodies such as CD16+56 +obtained from IQ products Co., the Netherlands.Results: In this project, the percentage of NK cells in the total patients and the control group were significantly different (p=0.01) and also the similar results were obtained with patients who respond to treatment after first period of medication (p=0.02) and those who did not (p= 0.04). Meanwhile, in our study the percentage of NK cells of the whole patients was not significantly different, before and after the treatment. In patients who were sensitive to the treatment and in those who were not the percentage of NK cells were not differing significantly as well.Conclusion: These results suggest that decreased number of NK cells in patient at risk of cutaneous leishmaniasis may increase the infection risk. And also suggest that Glucantime does not affect on the percentage of NK cells in the treatment of the patients.

Objective: Helicobacter pylori (HP) infection is the most common gastrointestinal bacterial disease worldwide. It is known that HP could be eradicated by a combination of therapeutic agents, but sometimes the cure thus achieved is incomplete and undesirable side effects are certain to occur. On the other hand, the anti- Helicobacter pylori effect of traditional herbal medicines has not been extensively studied. Cumin and tarragon are plants that are native to Iran and it has been reported that they are beneficial in gastric problems. In this study their activity against HP was examined.Materials and Methods: Percolated methanol and aqueous extracts of plant leaves were tested against 45 clinical isolates of HP. Growth inhibition was determined by the filter paper disc diffusion method on modified egg yolk emulsion agar (EYE agar) compared with amoxicillin and metronidazole.Results: The effect of both methanol extracts of cumin and tarragon were significantly better than their aqueous extracts (p<0.001). Methanol extract of tarragon and aqueous extract of cumin exhibited the most and least anti-HP activity, respectively. The minimum inhibitory concentration (MIC) of methanol extract s of cumin and tarragon were 691μg/ml. Both of two methanol extracts preserved their anti-HP activity after autoclaving for 20 min. Preliminary phytochemical screening of the cumin methanol extract indicated the presence of saponins and in the tarragon methanol extract indicated presence of saponins and tannins.Conclusion: Screening among natural resources and plants, which are used in folk medicine for gastric problems could be beneficial. This study demonstrated that tarragon and cumin inhibited the growth of H. pylori strains in vitro.

Objective: Cosmic radiations from outer space are continuously exposing the earth. Ambient dose rate at the atmosphere, apart from unusually and transient solar activities, is mostly a function of latitude and altitude. At aircraft altitude and temperate latitudes, it increases by a factor of 20-25. Therefore, aircrew and frequent flyers are exposed to high levels of cosmic radiation. This paper considers general radiation protection aspects of cosmic radiation exposure to aircrew in domestic flights in Iran.Materials and Methods Ambient dose rate in several domestic flights was measured using survey meter model RDS-110. Based on the measured data and duration of the flight, the effective doses of the aircrew were calculated and compared with that derived from radiation transport codes of CARI-6 introduced by Civil Aerospace Medical Institute, Oklahoma City, USA. Due to good agreement between measured and calculated values, the CARI-6 program was used to determine the dose rates in different altitude throughout the country to provide a simple algorithm for calculating route dose in domestic flights.Results: Equivalent dose rate in domestic flight's altitude can be calculated from, a(h)b where h is the altitude in thousand feet; a and b are constants depending to geographic location. Based on the equivalent dose rate and the flight profile; simple algorithm provided to estimate the route dose in any domestic flights.Conclusion: The annual dose limit of general population allows the aircrew to spend 290 hour in 27-33 thousand feet altitude in domestic flights; therefore, only female aircrew should be made aware of the need to control doses during pregnancy.

Objective: Melanoma is among the top six cancers as a cause of death and morbidity. Unfortunately there has been little progress in the medical treatment of metastatic melanoma, because of its resistance to current chemotherapeutic agents. In view of this, there is much interest in the identification of new agents for the treatment of melanoma. Rose Bengal (RB) has been used as a systemic diagnostic of hepatic function, ophthalmic diagnostic and photosensitiser in photodynamic treatment. In the present study, effects of RB, not as a photosensitiser, was tested in melanoma cells in the absence of light.Materials and Methods: Human melanoma cell lines, Me4405, Me1007, IgR3, Mel-FH, Mel-RM, Mel-CV, MM200, Sk-Mel-28 and fibroblast cells were cultured in DMEM medium. Cell death was quantitated by MTT assay. Apoptotic cells were determined using PI staining of DNA fragmentation by flow cytometry (sub-G1 peak).Results: The result showed RB could induce pronounced cell death in different melanoma cell lines but not in fibroblast cells. This toxicity was predominantly induced by non-apoptotic cell death but in some cell lines, RB could also induce apoptotic cell death.Conclusion: RB may be considered as a promising chemotherapeutic agent for the treatment of melanoma in the future.